1. Field of the Invention
The present invention relates to a magnetic head used for reproducing information from a tape magnetic recording medium employed in a VTR (video tape recorder), a digital VTR or the like, a method of manufacturing the magnetic head, and a magnetic recording/reproducing apparatus employing the magnetic head.
2. Description of the Related Art
In later years, with the progress in digitalization of image signals and computer-related technology, the amount of information increases exponentially. In a digital VTR or a tape streamer device for accumulating, storing an reproducing such a large amount of information, in order to improve performance of a magnetic recording/reproducing system therein so as to deal the large amount of information at high speed and promptly, research and development for providing the magnetic recording/reproducing system with a multi-head, a high-speed rotating drum, a narrow track, and a short wavelength have been made.
However, as for the inductive-type magnetic head which has been used widely, since the magnetic resistance of the head cannot be unlimitedly reduced due to the limit of the capability of the head itself, for example, physical limit of the permeability of a magnetic material, it is quite difficult to largely improve a real density thereof.
Therefore, attempts have been made to utilize a magnetic head employing an MR element utilizing the magnetoresistive effect, in place of the conventional inductive head, in a magnetic recording/reproducing apparatus using a magnetic tape, such as a helical scan system.
By the way, as shown in FIG. 10, in a case of using a magnetic head 102 employing a shield-type MR element on a rotary head drum 101 in a magnetic recording/reproducing apparatus, a slide-contact surface 102a of the magnetic head 102 is exposed toward a magnetic tape 103, and the magnetic tape 103 is in slide-contact with the slide contact surface 102a. Herein, an exposed amount δ of the slide-contact surface 102a of the magnetic head 102 from an outer peripheral of the rotary head drum 101 is called “head projection amount”. On the other hand, since output intensity of the magnetic head 102 is substantially inversely proportional to an MR head height h (refer to FIG. 6), the MR head height is preferably as small as possible. Usually, the MR head height is set in a range of 0.5–3 μm.
As shown in FIG. 11A, a curvature in a width direction of the slide-contact surface 102a of the magnetic head 102 is formed to be Rx, while, as shown in FIG. 11B, a curvature in a thickness direction of the slide-contact surface 102a of the magnetic head 102 is formed to be Ry.